Several people have been taken to hospital to receive treatment for injuries caused by a protester who parachuted into the Allianz Arena during France's win over Germany.European football's governing body Uefa said "law authorities will take the necessary action" for the "reckless and dangerous" act.
Debris fell on to the pitch and stands when the parachutist got tangled in wires carrying an overhead camera.
The man landed heavily on the pitch.
Greenpeace campaigner Benjamin Stephan said the plan was to "fly over" the stadium and release a light ball with a message encouraging German car manufacturer Volkswagen "to do more to protect the climate".
It added that "safety is at the heart of Greenpeace's action" and it will support any investigation.
This inconsiderate act - which could have had very serious consequences for a huge number of people attending - caused injuries to several people attending the game who are now in hospital and law authorities will take the necessary action," the governing body added.France won the game 1-0 courtesy of Mats Hummels' own goal in the first half.